According to new research on the hormonal changes in men and women during sadomasochistic parties, activities like spanking, flogging, and bondage are stressful while they are occurring, but can increase the bond between couples afterwards.

Researchers at Northern Illinois University measured the levels of the stress hormone cortisol during an S&M party and found that stress levels rose for the receiver during the scene, but returned to normal within 40 minutes. At another S&M event, researchers found that testosterone levels rose only in receiving women, which may happen to help women cope with the stress of the event. The couples reported increased relationship closeness afterwards and scientists say their findings show consensual sex is not stressful overall, even when it is extreme. But, if you're looking to get closer to your partner without breaking out the riding crop, psychologist Richard Wiseman says any shared activity will do the trick. "It doesn't have to be tying up your partner or placing clamps on their nipples, it could be something as simple as cooking a meal together or even doing the housework as a duo," he says. [The New Scientist]